Key-operated mechanical locks are well known and used for a variety of purposes, to secure a wide variety of objects. By far, the most common design is the pin-tumbler lock, which has proven popular on account of simple construction and ease of operation.
Conventional pin-tumbler locks have split-pins, wherein the pins restrain a first portion of the lock, commonly referred to as a cylinder, against rotation with respect to a second portion of the lock, commonly referred to as a housing, until the pins are moved in a position where the two halves of each split pin straddle a shear line, thus allowing rotation of the cylinder with respect to the housing. However, the vast majority of pin-tumbler locks are susceptible to lock-picking by manipulation of their pins to the shear line by objects other than the key which corresponds to the lock. Over the years, numerous designs have been proposed to address this problem with varying degrees of success. However, the vast majority of these devices are ineffective.
It would thus be desirable to have a key-operated mechanical lock that is of simple construction, easy to use, and which addresses the problems attendant to the prior art.